Accelerator.



1. E. THOMPSON & 131W. mmssour- ACCELERATOR.

APPLICATION FIND DUT- 7. 1915.

1,256,950. Patehted-Feb.19,1918.

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UNITED s rnrrns PATENT orrion.

JOHN E. THOMPSON AND CLARENCE W. JAMESON, OF CHICAGO, ILLINOIS, ASSIGNORS TO THOMPSON & JAMESON, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

ACCELERATOR.

Application filed. October 7, 1915.

To all whom it may concern:

Be it known that. we, J OI-IN E. THOMPSON and CLARENCE T. Lawson, citizens of the United States of America, and residents of .Chicago, Cook county, Illinois, have invented a certain new and useful Improvement in Accelerators, oi which the following is a specification.

Our invention relates to improvements in motor controlling devices, and has more particular reference to that type of controlling device generally known as accelerators, used in connection with the control of elevator motors and the like.

One of the objects of our invention is to provide an improved device of this character which will be simple, durable and reliable in construction, and effective and etlicient in operation.

Other objects of our invention will appear hereinafter.

Our invention consists in the features of novelty exemplified in the construction, combination and arrangement of parts hereinafter described, shown in the accompanying drawings, and more particularly pointed out in the appended claims.

In the drawings:

Figure l is a front or face view of an accelerator or controlling device embodying our invention; and

F ig. 2 is a View substantially in section on the line 22 of Fig. 1.

The device which we have illustrated in the drawings and which embodies our in vention is designed more particularly for use in connection with elevator motor control, but it will be obvious to one skilled in the art, after having obtained an understanding of our invention from the disclosures herein made, that the structure may be modified or adapted for other and different use without departing from the scope and spirit of the invention.

The parts of the structure herein shown are mounted upon supporting board A or panel, which obviously may, if desired, form the front of a suitable box or casing containing the resistance R. \Ve have, however, simply shown the resistance R in diagram for the sake of clearness.

the fron of the supporting panel A Specification of Letters Patent.

Patented Feb. 19, 1918.

Serial No. 54,625.

is a plurality or series of switches B which are arranged in a row, the switches being vertically disposed and in parallel relation.

Each switch has a fixed contact B which in the present structure is in the form of a cylindrically-shaped piece of carbon supported in suitably shaped bracket 1 bolted to the panel A, the bolts extending through the panel and carrying nuts 2 on their rear ends so as to form suitable terminals on the rear of the board to which the conductors may be attached. The carbon blocks B extend forwardly from the boarc A and. their ends rest against the face of the board so as to provide a substantial backing to take the strains incident to the closing of the switch. Each contactis fastened rigidly to its bracket by a bolt 3 extending through it and into the bracket. The switch arms C at their lower ends have lugs or cars so that they may be rotatably or pivotal] y mounted side by side in a common shaft 4:. Thus they swing toward and from the fixed contacts B in parallel planes, which in this case are perpendicular to the plane oil the panel board 2. The shaft 4: is supported in proper position by a horizontally disposed bar or member 5 having outstanding projections or lugs (3 at its ends in which the ends of the shaft at are mounted. This construction permits convenient assembling and disassembling of the switches and enables a d ranged switch to be replaced without disturbing the rest of the parts. The bar or member is fastened to the supporting panel A in any suitable manner, and in addition to serving as a support for the switches also constitutes a conductor common to all of said switches. In order, however, to insure a suitable electrical connection between each movable switch and the common member 5, we provide a flexible conductor, such as a flexible cable or strip of copper 7, for each switch. These conductors 7 are connected at one end by the screws 8 to the common member 5, and at their other ends by the screws 9 to the respective switch. arms C. Extending between the lower corners of the ears 6 of the bar 5 is another bar 5 which, being below the pivotal points of the switch arms, serves as a bumper bar to limit the outward or opening movement of the switches; and

switches.

in order that this limit of movement may be adjusted, we provide an adjusting screw or bolt 10 for each switch. This adjusting bolt is threaded through the bar 5, and is engaged by the portion 11 of the switch arm which lies below the pivotal shaft or rod Each adjusting bolt may have lock-nut 12 thereon by which it may be locked in its adjusted position. Atits upper end each switch arm is broadened and formed as a sort of yoke, so as to form a substantial seat for the contact piece 13 which is held in its seat by a bolt 14 extending through the contact piece and threaded into the yoke at theuppcr end of the switch arm. These contact pieces 13 are cylindrical in shape and made of carbon similar to the fixed contacts B and are arranged, when the switch is closed, to abut against the ends of the fixed contacts B This type of contact provides a comparatively large area of conducting surface between the respective pairs of carbon pieces 13 and B of each switch, and renders it practically impossible for the switches to stick or fail to open-that is, this form of contact offers no resistance to the opening of the switch. Each switch arm has another section or extension. member 15 which is pivoted. at 16 between the pair of lugs on the switch arm and which extends to a point below a pivotal point of the switch arm. At its lower end this extension carries a roller 17. The extension or section member in this case is yieldingly held against the switch arm C by a spiral spring 18 which bears against the section 15. This spring is held under compression between the section 15 and a nut and washer 19, carried on the end of a rod or bolt 20. The rod or bolt 20 is fastened to the lower end portion 11 of the switch arm 0 and extends through a suitable opening in the section 15. The nut on the outer end of the rod is adjustable thereon so as to vary the action of the spring. The arm C and the section 15 thus, in a sense, form a single arm for rotating the switch about its pivot to close it into contact with its respective fixed Contact 13 and an outward force exerted on the extension C below the pivotal point of the switch will throw the switch or spring it about its pivotal point into engagement with its respective fixed contact B. After it engages its contact B if the force still continues the spring will yield to accommodate it. In this manner the switch is held firmly, yet 'yieldingly, against its contact. The switches are closed against their fixed contacts by a common actuator bar or member 21, which in the present construction. mores in a plane part. lel to the face of the panel board; or, stated in another way, it moves in a plane at an angle to the planes of movement of the l. T hisactuator bar is so arranged late its resistance to the pull of the solenoid that it will engage the rollers 17 on the switch extensions 15, and by reason of a side thrust or wedging action, so to speak, on said rollers will apply a force in the direction to swing said switches into engagement with their contacts. One end 22 of the arm is pivoted in a suitable bracket 23 secured to the panel board A, this pivotal connection being formed by reducing an end portion of the bar 21 and placing this reduced end portion in a suitable hole in the bracket 23. The actuating member 21 of itself operated, or may be moved, about its pivotal point in any suitable manner, but in our construction we provide a solenoid or eleotromagnet D of any suitable or approved type. This solenoid is mounted on the panel board A. and opera tcs its core D vertically. The other end of the actuator bar is pivotally connected at in any suitable manner tothe core of the set noid, and is thereby swung or moved about its pivot. In order that the switches may be operated successively, the actuator bar is di posed, as shown in Fig. 1, at such an angle that in swinging about its pivot it engages the roller of the switches in successsive order, beginning with the switch nearest the pivotal point of the actuator bar. Thus a slight movem nt of the actuator bar will throw in the first switch 1, and a still further movement will. throw in the second switch, and so on until all of the switches will be thrown against their contacts. T he actuator bar is rectangular, and its upper outer edge is slightly round. I is so disposed with spect to the roller that it engages the roller and thrusts or forces it outward, thus closing the switch. hen the switch is closed, the roller rides against the outer faces of the actuator bar while the next switch in the series is being closed, and in this manner the actuator bar not only closes each switch, but holds it in closed position. The arrangement of the switches in sections which are relatively yieldable not only allows for any slight inaccuracies of manufacture and adjustment, but also reduces the effort of the solenoid to operate the switches and it also prevents the binding of the parts which would be the case if the switch arms were made rigid. This is obvious since any tendency of the actuator bar to bind when op erating a switch is offset by the yielding of the lower section 15 after the switch has closed against its contact.

in order to govern the speed at which the solenoid may actuate the actuator bar,

we provide a dash pot E of any suitable or apprcwed type. In the structure shown. the piston rod of the dash pot is connected to the lower end of the solenoid core, as shown clearly in the drawings, and the dash pot is provided with a suitable valve 31 to reguand thereby regulate the speed atwhich the solenoid actuates the switches.

The accelerator switch in this case is used for gradually decreasing the amount of resistance R in the circuit of the motor. e have shown the resistance R diagrammatically. e provide a series of terminal or binding posts 32 to which the connections may be made. The various electrical conneetions for our improved accelerator need not be particularly described except to say that they are so arranged that tie switches successively shunt or short circuit portions of the resistance R included in the armature circuit. lVe have, however, shown these connections as they are made when the accelerator is used in conjunction with the reversing switch which constitutes the subject matter of our co-pending application, Serial No. 59,144, filed Nov. 1, 1915, the reversing switch and the accelerator switch being jointly used in the control of the elevator or other motor. It is, or course, understood that our improved accelerator may be used alone or in conjunction with other types of reversing switches without departing from the scope and spirit of our invention.

hat we claim as our invention is:

1. The combination of a supporting panel having a plurality of contacts, a plurality of pivotal switch arms cooperating therewith and movable toward and from said contacts, and a common actuator member pivotally mounted at one end and movable in a plane transverse to the plane of movement of said switch arms and arranged to successively engage and actuate said arms and means for swinging said bar about its pivot.

2. The combination of a support, a plurality of switches thereon arranged side by side and movable in parallel planes, a bar pivoted at one end on said support and arranged adjacent said switches and movable in a plane at an angle to the planes of movement of said switches to engage the switches and operate them, and electromagnetic means connected to the other end of said bar for moving said bar about its pivot.

The combination of a switch comprising pivotally connected relatively yield-able sections, a contact with which one of the sections cooperates, and a movable cam bar pivoted at one end and arranged to engage the other section of said switch to close the switch against its contact.

l. The combination of a pivotally mounted switch arm, a contact with which the switch arm engages, a yielding extension on said switch, a bar pivoted at one end and movable about its pivot to engage said yieldable extension and close the switch against its contact, and means for actuating said bar.

'5. The combination of a plurality of rela tively fixed contacts, a plurality of pivoted switches movable toward and from said contacts, a yieldable extension on each switch extending beyond the pivot oi said switch, a bar pivoted at one end and movable about its pivot in plane transverse to the planes of movement of aid switches, and an electromagnet for moving said bar successively into engagement with said extensions to force the switches against their contacts.

6. The combination of a plurality of fixed contacts, a plurality of pivoted switches forming levers adapted to move to and from said contacts, and each comprising yield ably related sections having portions extending beyond their pivots, a pivoted cam bar angular-1y disposed with reference to the projecting portions of said switch levers and adapted when moved about its pivot to sue cessively engage said projecting portions and close the switches, and an electromagnet tor moving said cam bar about its pivot.

7. The combination of a plurality of fixed contacts, a plurality of pivoted switches forming levers adapted to move to and from said contacts, and each comprising yieldably related sections having portions extending beyond their pivots, a pivoted cam bar angularly disposed with reference to the projecting portions of said switch levers and adapted when moved about its pivot to suecessively engage said projecting portions and close the switches, an electromagnet for moving said cam bar about its pivot, and limit stops for normally holding said switches in proper position with respect to said cam bar.

8. The combination of a supporting banel, a plurality of fixed contacts on said panel, a plurality of switch levers freely movable toward and from the contacts, each switch lever comprising pivotally related sections, a cam bar pivoted at one end on said supporting panel and disposed at an angle to the ends of saic switch levers so that when swung about its pivot it will successively engage the ends out said levers and force them into engagement with their fixed contacts, and spring mechanism between the sections of each lever, adapted to yield to the action of the cam bar when the switches are in cngagei -ent with their contacts.

9. The combination of a supporting panel, a plurality of fixed contacts thereon, a plurality of switch levers movable in parallel planes toward and from said contacts, a common bracket on said panel having a rod common to all of said switches and forming a pivot therefor, an extension arm pivoted on each switch and extending below said pivot rod, a bar pivoted on said panel and disposed at an angle to the ends of said extensions so that when moved about its pivot Signed by us at Chicago, Illinois, this 2nd day of October, 1915.

JOHN E. THOMPSON. CLARENCE W. JAMESON.

Witnesses H. CLEGG, AMY JEHLE.

Gopies at this patent may be obtained for five cents each, by addressingthe Commissioner of Yatents,

Washington, D. G. 

